Method for converting cyclic polycarbonate oligomer mixtures to linear polycarbonate, and composition resulting therefrom

US4740583A · kind A · utility

Assignee

• General Electric Company · US

Inventors

• Daniel J. Brunelle · Scotia, US
• Thomas L. Evans · Clifton Park, US
• Michael Alan Vallance · Loudonville, US
• Kevin R. Stewart · Schenectady, US
• Thomas Gerard Shannon · Neenah, US
• David A. Williams · Scotia, US
• Dwight J. Patterson · Murfreesboro, US
• Niles R. Rosenquist · Evansville, US
• William Hilakos · Greenwood, US

Key dates

• Filing date: Jul 24, 1986
• Grant date: Apr 26, 1988
• Expiry date: Jul 24, 2006

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2369/00
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Cyclic polycarbonate (or thiol analog) oligomer mixtures are prepared by the reaction of bishaloformates or their thio analogs, or mixtures thereof with dihydroxy or dimercapto compounds, with alkali metal hydroxides and various amines. The oligomer mixtures may be converted to polycarbonates or their thiol analogs by a method which is particularly adaptable to integration with polycarbonate processing operations. Polymerization may be conducted simultaneously with molding, extrusion and the like. The oligomer mixtures are adaptable to the preparation of filled prepregs.